MELVILL: GENERA I'SEUDOI.IVA AND MACRON. 



325 



seas, various Ancillce and BtillicB, some exhibiting a certain similitude 

 to it in form, texture, or coloration; but all in reality far removed 

 from it. Always found in more or less worn condition, as are so many 

 South African mollusca, the surf-laden seas being subject to violent 

 tempests and gales, the outer lip of P. aficilla is usually imperfect, and 

 such was the condition of the specimen figured by Mr. Sovverby (/.^.), 

 accordingly it is uncharacteristic. 



It is not easy to say whether, in life, the surface is covered by an 

 epidermis, but if there be one, it is probably of thin texture. The 

 operculum is unknown; nor have the soft parts been yet studied. Not- 

 withstanding this, I venture, on conchological grounds, to describe it 

 as pertaining to a new genus, and would predict that justification for 

 this step will ultimately be found. I have not yet noted any fossil 

 form coming near this species, which stands alone, as already re- 

 marked, for peculiarity of form. 



Sylvanocochlis gen. nov. 

 Shell very smooth, dun coloured, imperforate, fading into white in 

 the centre of the last whorl, somewhat solid, spire attenuately fusiform, 

 whorls compressedly flattened, not the least channelled at the sutures, 

 mouth ovale-oblong, outer lip thin, possess- 

 ing a tooth-like projection, near the base, at 

 the point where commences the spiral groove 

 extending over the last whorl to the colum- 

 ellar margin. This last almost smooth, white, 

 shining, with a shining noduled callus in 

 the upper part. 



Type 6". ancilla Hanley. 

 Long. 46 mm., lat. 25 mm. Hab., South 

 Africa (Kaffraria, Hanley). 



The whorls are 5-6 in number, the two 

 uppermost apical, smooth, somewhat bulb- 

 ous, the rest compressed towards the centre, 

 and so slightly sinuous, the last whorl below 

 the suture compressedly constricted, thence 

 to the base more gradually sloping, fawn 

 coloured fading into a white indistinct fascia 

 in the centre of the last whorl. The mouth 

 is channelled above, at the junction of the columellar with the outer lip. 

 I have seen several examples of this curious shell, but consider the 

 one now taken for the type of the new genus Sylvanocorhlis, though 

 not quite perfect, more so than any other probably now extant; the 

 outer lip being characteristic. The generic name is given in honoured 

 memory of the describer of the species, the late Mr. Sylvanus 

 Hanley, F.L.S. 



Sylvanocochlis ancilla. 



